Hey when you going to frag. that blue sponge.... I also thought that blue sponges were photosynthetic.BINGO..... RUN!!!!! Do not look back, just RUN. LOL
This is not true for all sponges. This was the first that I heard of. I have red tree sponge, yellow ball sponge, orange fan sponge, some blue sponge in my tank. If your tank is new, sponges may not be the best as they are filter feeders and non-photosynthetic the amount of nutrients they need can throw your system off. I believe Bongo Shrimp has a beautiful photosynthetic sponge for sale that I would snatch up in a heartbeat if I had the space in my tank.